Checks if an association between two DAG nodes already exists, i.e.
does not need to be introduced when adjusting for a shared child etc.
Internally called by dag.adjustment
.
assoc.exists(dag, a, b)
A boolean indicating whether or not an association between first node and second node already exists.
The DAG to be dealt with.
First node.
Second node.
Lutz P Breitling <l.breitling@posteo.de>